DENVER – A high intake of insoluble dietary fiber is associated with reduced inflammation and all-cause mortality in patients with chronic kidney disease, results from a large observational analysis showed.
The finding underscores the importance of a fiber-rich diet in this patient population, which often presents with a low intake of dietary fiber, Dr. Neelakanta A. Dadi said in an interview during a poster session at the annual meeting of the American Society of Nephrology.
Dr. Neelakanta A. Dadi
“I think this study tells us that patients with chronic kidney disease need to consume more dietary fiber such as vegetables, fruits, and oatmeal,” said Dr. Dadi of the University of Utah, Salt Lake City.
He and his associates used the National Health and Nutrition Examination Survey III to evaluate the association between elevated C-reactive protein (defined as greater than 3 mg/L) and all-cause mortality in 1,105 patients with chronic kidney disease. The researchers estimated intake of insoluble dietary fiber from 24-hour recalls and obtained mortality data through the National Center for Health Statistics by linkage with National Death Index records through 2006.
Low total dietary fiber intake was defined as less than 13.5 g/day while high dietary fiber intake was defined as 13.5 g/day or greater.
The mean age of patients was 69 years and 36% were male.
In a multivariate logistic regression analysis adjusted for age, sex, race, smoking, alcohol, systolic blood pressure, diastolic blood pressure, cancer, physical activity, calorie intake, protein intake, myocardial infarction, heart failure, and stroke, each 10-g/day increase in dietary fiber was associated with a significantly decreased odds of elevated serum C-reactive protein and all-cause mortality (OR, 0.56 and 0.80). A similar association was seen after further adjustment for waist circumference, diabetes, triglycerides, and HDL cholesterol level (OR, 0.56 and 0.76).
Dr. Dadi said that the observational design of NHANES III is a limitation. “It remains unclear what the major cause of mortality is in this population,” he said. “It could be cancer or cardiovascular events.”
The study was funded by a National Kidney Foundation Fellowship Grant and by grants from the Public Health Service and the National Center for Research Resources.